Based on Bairoch (1990)&      -17.71\sym{***}&      -26.66\sym{***}&        4.53         &       13.49\sym{***}&      -13.17\sym{***}\\
            &      (3.41)         &      (4.64)         &      (3.48)         &      (2.55)         &      (4.81)         \\
            &      [3.30]&      [5.56]&      [3.58]&      [2.60]&      [5.10]\\
Squared transport costs&      -27.59\sym{***}&      -32.14\sym{***}&       10.04\sym{***}&       14.58\sym{***}&      -17.56\sym{***}\\
            &      (6.50)         &      (6.52)         &      (3.24)         &      (3.07)         &      (6.58)         \\
            &      [5.66]&      [6.06]&      [3.47]&      [3.08]&      [6.09]\\
Only larger river&      -30.19\sym{***}&      -33.56\sym{***}&       13.04\sym{***}&       16.41\sym{***}&      -17.16\sym{**} \\
            &      (7.60)         &      (7.29)         &      (3.28)         &      (2.99)         &      (6.71)         \\
            &      [5.68]&      [5.93]&      [3.04]&      [2.97]&      [5.67]\\
Log access to carboniferous strata, Daudin &      -17.53\sym{***}&      -24.44\sym{***}&       -0.47         &        6.44         &      -18.00\sym{**} \\
            &      (5.99)         &      (5.43)         &      (8.58)         &      (6.28)         &      (8.37)         \\
            &      [6.52]&      [5.53]&      [8.46]&      [6.21]&      [9.10]\\
Log access to carboniferous strata, Bairoch &      -21.13\sym{***}&      -31.71\sym{***}&       -1.75         &        8.83\sym{*}  &      -22.88\sym{***}\\
            &      (5.56)         &      (6.85)         &      (7.65)         &      (5.01)         &      (8.82)         \\
            &      [5.86]&      [7.12]&      [7.29]&      [4.74]&      [9.04]\\
Accounting for coal fields in 1967&      -28.77\sym{***}&      -32.64\sym{***}&       11.63\sym{***}&       15.50\sym{***}&      -17.14\sym{**} \\
            &      (6.78)         &      (6.97)         &      (3.11)         &      (2.93)         &      (6.89)         \\
            &      [5.08]&      [5.73]&      [3.06]&      [2.95]&      [5.91]\\
